1. Field of the Invention
The present invention relates to an optical deflector using a MEMS (Micro Electro Mechanical System) technique and a method of driving the same.
2. Description of Related Art
In recent years, there has been an increase in the development of a microactuator using a MEMS technique. For example, an optical deflector provided with a mirror supported for torsional rotation by a pair of elastic support portions (torsion bars) has been developed as a device that can form an image display device with a simple configuration.
With a recent increase in area of a mirror, the moment of inertia of the mirror has been increasing, resulting in a problem in that driving torque rises. JP-A-2004-037886 discloses a configuration of an optical scanner in which a back surface of a mirror is provided with lightening portions.
However, as described in JP-A-2004-037886, even though the back surface of the mirror being provided with the lightening portions definitely reduces the moment of inertia, there remains a problem in that elements such as a magnet, a coil and a sensor cannot be arranged on the back surface of the mirror.